


the water's sweet but blood is thicker

by WendigoBaby



Category: Shadowhunters (TV)
Genre: Background Simon Lewis/Isabelle Lightwood, Bisexual Isabelle Lightwood, F/F, Gen, M/M, Protective Alec Lightwood, Sibling Bonding, alec and izzy hang out and talk that's the whole thing, and they tease each other about respective love lives
Language: English
Status: Completed
Published: 2017-08-29
Updated: 2017-08-29
Packaged: 2018-12-21 11:00:51
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,633
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11942745
Author URL: https://archiveofourown.org/users/WendigoBaby/pseuds/WendigoBaby
Summary: Izzy's had a bad day ending with an even worst date and the best cure for being blue is talking to her favorite big brother.





	the water's sweet but blood is thicker

**Author's Note:**

> i've been having a lot of feelings about these two and they are my favorite sibling relationship on the show, so this is a short piece about how they interact and how much they love each other in an everyday situation :' )
> 
> (title is from hey brother by avici)

Crossing the Institute’s threshold, Izzy immediately knows where she’s headed as the heavy doors swing closed behind her. It’s been a crap day, her mission going awry and then the rest of her day following the trend, making her more tired than usual. She could just go and relax in her room, put her hair up and read, head over to Clary’s room and rant about everything wrong in the world or see what her rascal of a little brother is up to, but she doesn’t. 

 

She passes by the training room and greets Jace with a wave and a smile. He salutes back before going back to wailing on the punching bag. 

 

It’s quiet, the clicking of Izzy’s heels announcing her presence before she even reaches the room. All the electronics in the OPS centre hum in unison, the blue hue from the screens reflecting against the buckles on her boots when she moves past them. A few stray Shadowhunters swipe across holographic displays of New York, looking focused. One or two pick up their heads and nod at Izzy before going back to their tasks. 

 

For once, Izzy is glad for the lack of attention. Her ankle keeps sending out waves of dull pain up her leg, even after a generous use of an Iratze, it’s something anyone could notice and she doesn’t feel like explaining herself.

 

A few corridors into the depths of the cathedral, Izzy stops in front of the Head’s Office, an elegant gold plaque adorning the wood. It’s kind of late, but she’s sure her brother is still working, chin-deep in various paperwork. The door is cracked-open, warm light spilling into the hall as she drums her fingers on the doorjamb, various rings clinking against the wood, before coming in. 

 

And she’s right - when she steps inside, Alec’s at his desk, hunched over a tablet filled with a wall of text; a stack of beige folders looms over at his side, a half empty coffee cup is dangerously positioned right next to them and his jacket sits over the back of the swivel chair. Alec doesn’t seem to have noticed her yet, lost in his job with the tip of his tongue trapped between his lips, fingers rubbing together in a way she’s seen Magnus do before. 

 

“Earth to Alec?” she says, eyebrows raised and voice half-mocking. 

 

His head snaps up and the sour expression etched into his skin dissolves into a soft curious smile, eyes twinkling in the light from the desk lamp.

 

“Izzy, hi. I didn’t hear you come in,” with a sigh, he lifts himself from his chair stiffly and she can hear his spine crack, which just confirms Isabelle’s suspicion that he probably didn’t give himself time for a break since dinner. 

 

“You were so focused you wouldn’t hear a horde of demons running through the Institute. Five minutes of rest wouldn’t kill you, big brother,” she quips back and Alec almost looks chastised before rolling his eyes at her. 

 

A twinge of guilt goes through his expression, but then he’s in front of her with his arms open and it’s just what Izzy needs. She wraps her arms around him, hiding her face in his chest; he’s warm and familiar, soothing in a way, his hands petting down her curled hair and coming to rest against her back. All of the stress from the day flows out of her to the rhythm of his heartbeat, when she puts her ear over his sternum. 

 

“What’s wrong?” Alec asks, before pressing a kiss against the top of her head.

 

“Nothing’s really _wrong_ , the universe is just out to get me today.” 

 

“Wanna talk about it?”

 

Izzy steps back with a nod and Alec leads her to the couch with a palm on her back, turning on one of the lamps along the way. It bathes the other half of the spacious office in warm light and the crackling of the fireplace makes it even cozier. They sink into the cushions and Izzy has to admit - one of the perks of having a brother who’s a Head is being able to lounge on one of the most comfortable couches she’s ever encountered. She makes quick work of the buckles and zips on her shoes before she kicks them off with a breath of relief, wiggling her toes. She lies down, stretching the whole length of the couch and putting her legs in Alec’s lap, who rests his own on the coffee table in front.

 

“So what’s up?” Alec asks, always the worrisome oldest sibling. His hands rest on her calves, absentmindedly drawing runes and random shapes over the fabric of her jeans. With the way Izzy folds her hands over her stomach, it starts to feel like a free therapy session.

 

“During patrol we got ambushed by shapeshifters, but before you freak out, no one got hurt, it was just more stressful than I anticipated for 8:30 in the morning,” she laughs and watches Alec give her a lopsided smile, eyes rolling at her comment about him; they both know it’s true. “Then Lindsay was annoying me with dumb comments, and after that I had to chase down Max before he got out of the Institute again. Don’t even get me started on my date, oh god.” 

 

“You were going to see that Seelie, the one with the red hair, right?” 

 

Izzy nods and wrinkles up her nose as something warm curls in her chest over the fact Alec remembers these details. She shouldn’t be surprised, she knows he cares and he’s very observant overall, but it’s just nice to experience the attention he pays to her, being one of the few people that truly know her. 

 

“I’m guessing it didn’t go well?” he asks, tone nonchalant and a tiny bit curious.

 

The beginning of the date gave Izzy hope - they met up on time and the girl was gorgeous. She had white flowers adorning the edge of her jaw and her eyes were the same pretty shade of sea as when they met at Hunter’s Moon a week or so ago. But then it just went downhill; their conversation was stilted and awkward despite best efforts on both sides, as they didn’t have much in common, both personality and interest-wise. 

 

“It could’ve gone better. We just weren’t compatible and it was boring. Also, she smelled like garlic bread, so I felt like I was talking to an Olive Garden.” 

 

Alec chuckles and Izzy joins him; it feels almost like their evenings a few years back, when they were teens and they’d sit out on the Institute’s roof, just hang out with each other, brother and sister against the world.

 

“Just a fair warning, Magnus is going to hear this story,” Alec says through his snickering, and it’s such a married thing to say. Izzy knows Magnus has been away for a warlock council meeting in Barcelona for a few days already, but he and Alec have been talking on the phone, relaying all kinds of news and gossip as they would if they were home together. 

 

“I don’t mind, you tell him everything anyway,” Izzy replies and winks at her brother, who feigns innocence, lips pursed in quiet protest. Even if her dating world is empty for the time being, she still has Alec to tease about being head-over-heels. “Now that you mention your boyfriend, ask him if he has any single friends, would you? Maybe I’ll find my unending happiness with a gorgeous magicmaker just like you.” 

 

“I’ll ask,” Alec agrees, cheeks pink, but when Izzy glances up at him again from where she’s twirling a piece of hair around her finger, he looks like he wants to add something else, so she waits patiently.

 

It reminds her a bit of the conversation they had about sex, the same way Alec seems to be picking the right words, his mouth parted and eyes settled on something behind Izzy’s head.

 

“I can’t believe I’m saying this, but you… you got on well with Simon, didn’t you? You two seem good for each other. And I’m pretty sure he doesn’t smell like garlic bread.” 

 

Izzy can’t stop the grin spilling over her face and Alec looks exasperated before she even opens her mouth. 

 

“Is my big brother really trying to set me up with someone? Is this an alternate universe? What happened?” She teases dramatically and Alec pokes at her side in retaliation, before she can catch his fingers to stop the further assault on all of her ticklish spots. 

 

“ _Love_ happened. We switched places and now you’re the miserable one.” 

 

Izzy makes an offended expression, but she’s proud. She looks at her brother smiling ear-to-ear, openly talking about his feelings and joking with her when he used to scoff at her efforts to cheer him up. She knew Alec loved her whether he showed it or not, but actually witnessing him flourish into happiness and self-confidence is something priceless. 

 

“I’m not miserable, Alec, just lonely and slightly sexually frustrated.” 

 

Alec points at her with his free hand as if Izzy just confirmed his point and it’s her turn to roll her eyes with a groan. 

 

“To be fair, I lucked out on my first try. So...” he drifts off, glancing over to the pile of work still waiting to be done with almost palpable disdain. “How about we go to your room, drink wine, and watch some of those bad movies you like?” 

 

They smile at each other and Izzy pushes herself up and off the couch, barefoot on the wooden floors and hair messy from laying on it. She extends a hand to Alec and pulls him up, before linking their arms together in an exaggerated gesture.

 

“Sounds like a good time.”

**Author's Note:**

> You can find me on [tumblr](www.maghnvsbane.tumblr.com)! xx


End file.
